Circuit breaker



,Maich 31, 1936. w. H. FRANK ET AL CIRCUIT BREAKER Filed March 29, 1934INVENTORS wwwajmif BY t W A TORNEY,

Patented Mar. 31, 1936 PATENT OFFICE CIRCUIT BREAKER William 1!. Frankand Joseph Messing, Detroit, Mich, assignors to Bulldog ElectricProducts Company, Detroit, Mich, a. corporation of West VirginiaApplication March 29, 1934, Serial No. 717,989

12 Claims.

This application relates to circuit breakers, and discloses a novelholding means forv breaker trip pawls or levers, useful as a substitutefor holding means of the character disclosed in Pat- 5 cut No.1,982,289, November 27, 1934, Figs. 3-4.

Details of the constructions shown will be understood upon reference tothe following detailed descriptive matter which relates to the appendeddrawing. In this drawing,

Figures 1 and 2 show holding means for a breaker pawl, in elevation andtop plan view.

Figures 1 and 2 show novel holding means for breaker trip pawls orlevers, useful as a substitute for a holding means like the one shown at200-209, 2ll--2l3 of Patent No. 1,982,289, No-

vember 27, 1934, Figs. 3-4, to hold the end of a trip pawl or lever,like the end 88 of the pawl 81, pivotally mounted in the frame at 86.

On the base 66 is pivotally mounted at 2M a thermal warping element 282urged toward the base by a coiled tension spring 283 connected incircuit through the pivot hinge at 28 l, or through a flexible jumper,and adapted to warp on overload to the right. Secured to and disposedtransversely across and preferably insulated from the warping element isan E-shaped magnetic material piece 284 which, together with themagnetic material plate 285 mounted upon the pedestal 286, forms amagnetic circuit with the ther- 30 mal element 282 forming a single turncoil to provide the magnetomotive force.

A bracket 2M is rigidly secured to warping element 282 by rivets 262,there preferably being insulation 203 between the element and thebrackets. An arm 204 is pivotally connected to bracket 2M by a pinZOB-and is provided with a lock washer 206 which maintains arm 20; inany desired preset position, relative to the element. A pin 20! on theouter or free end of arm 204 rides freely in a circular slot 208 of alever-latch 209 pivotally secured to a foot 2| l bya rivet M2 and thusmounted on the base 50. A hook M3 on the upper end of latch 209 holdsthe breaker pawl 81 firmly when the breaker is in the on position, or inits normal 0 position.

When an overload occurs, the warping element 282 moves to the right, dueto thermal forces, or magnetic forces, or a combination of both forces.This motion is magnified by the leverage ratio 50 provided by the leverlatch 209 moving the hook end 213 thereof to release the pawl 81.

Now having described an embodiment of the 5 invention.

mounted that it may move bodily in accordance with stresses exertedthereon by the magnet.

2. For use in a circuit protective breaker havl5 ing means normallytending to move parts into release condition when they are in resetcondition and a pawl which when held prevents such action of the means,a holding means for said pawl including a circuit current controlledther- 20 mally responsive element which deflects by warping on overloadinto pawl releasing position and is mounted to move bodily regardless ofdeflection, and a circuit current controlled magnet for moving theelement bodily and instantaneously 25 I into pawl releasing position onan overload of suficient magnitude to operate the magnet.

3. For use in a. circuit protective breaker having means normallytending to move parts into release condition when they are in resetcondi- 30 tion and a pawl which when held prevents such actionof themeans, a. holding means for said pawl including a circuit currentcontrolled thermally responsive element which deflects by warping onoverload into pawl releasing position and 35 is mounted to move bodilyregardless of deflection, and a circuit current controlled magnet formoving the element bodily and instantaneously into pawl releasingposition on an overload of sufficient magnitude to operate the magnet,the 40 holding means also including a holding latch connected to theelement by a movement amplifying connection and operating directly onthe pawl.

4. In a circuit protective device, a circuit ourrent controlled delayedaction holding element, and a magnet carried by and forming part of theelement for causing instantaneous movement of the element on overload,the element being so mounted that it may move bodily in accordance withstresses exerted. thereon by the magnet, the element being an energizingsource for the magnet.

5. A holding and releasing means for a circuit breaker part comprising athermally responsive element, movement amplifying means positivelyconnecting the element to the breaker part whereby overload warping orreturn cooling of the element will cause amplifled movement of thebreaker part, the current in said element providing a magnetic forceauxiliary to the thermal force for releasing the breaker, the elementbeing mounted to move bodily regardless of deflection in accordance withmagnetic forces created by the current flowing through it.

6. A holding and releasing means for a circuit I breaker part comprisinga thermally responsive bimetal element, movement amplifying meanspositively connecting the element to the breaker part whereby overloadwarping or return cooling of the element will cause amplified movementof the breaker part, and means responsive to the current flowing in saidelement for creating a magnetic force which assists the thermal warpingforce for causing release movement of said element and thereby releasingthe breaker, the element being mounted to move bodily regardless ofdeflection in accordance with magnetic forces created by the currentflowing through it.

7. A holding and releasing means for a circuit breaker part comprising acircuit current controlled element constructed to deflect itself with adelayed action to release position on a circuit fault and to deflectitself automatically to holding position thereafter, and mounted on apivot hinge so as to be movable bodily to and from release and holdingposition regardless of deflection, and means operating on a circuitfault and against an adjustable resistance for, causing instantaneousmovement of the element bodily to release position.

8. A holding and releasing means for a circuit breaker part comprising acircuit current controlled element constructed to deflect itself with adelayed action to release position on a circuit fault and to deflectitself automatically to holding position thereafter,.and mounted on apivot hinge so as to be movable bodily to and from release and holdingposition regardless of deflection, and means operating on a circuitfault for causing instantaneous movement of the element bodily torelease position.

9. A holding and releasing means for aicir-' cult breaker D811;comprising a circuit current controlled element constructed to deflectitself with a delayed action to release position on a circuit fault andto deflect itself automatically sheaves to holding positionthereaften-and mounted on a pivot hinge so as to be. movable bodily toand from release and holding position regardless of deflection, andmagnetically actuating means operating on a circuit fault and against anamustable resistance for causing instantaneous movement of the elementbodily to release position.

10. A holdlngand releasing meansfor a circuit breaker part comprising acircuit current controlled element constructed to deflect itself with adelayed action to release position on a circuit fault and to deflectitself automatically to holding position thereafter, and mounted on apivot hinge so as to be movable bodily to and from release and holdingposition regardless of deflection, and magnetically actuating meansoperating on a circuit fault for causing instantaneous movement of theelement bodily to release position.

11. Means for moving a circuit breaker holding part comprising a circuitcurrent controlled element constructed to deflect itself with a delayedaction to move the part into release position on a circuit fault and todeflect itself automatically to move the part into holding positionthereafter, and mounted so as to be movable bodily to and from releaseand holding position regardless of deflection, and means operating on acircuit fault for causing instantaneous movement of the element bodilyto release position, the element being positively connected to the partthrough a movement amplifying connection so that minute movements of theelement will positively cause amplied movements of the part.

12. Means for moving a circuit breaker holding part comprising a circuitcurrent controlled element constructed to deflect itself with a delayedaction to move the part into release position on a, circuit fault and todeflect itself automatically to move the part into holding positionthereafter, and mounted so as to be movable bodily to and from releaseand holding position,

- and circuit current controlled magnetically actuating means operatingon a circuit fault for causing instantaneous movement of the elementbodily to release position, the element being -positively connected tothe part through a movement amplifying connection so that minutemovements of the element will positively cause amplifled movements ofthe part. 1

JOSEPH MESSING.

